The Furnace Is Out Cold? 8 Steps to Get It Up and Running Again

When your furnace is out, an after-hours service call is often substantially more expensive than an appointment during regular working hours. Prior to calling for an after-hours service technician, troubleshoot the furnace first to see if you can get it up and running.

Here are eight areas to check to get your furnace up and running again:

Thermostat: The thermostat is the brain of your heating system. If the device has been inadvertently shut off or the settings changed, the furnace may not work. Make sure you regularly change the batteries in the thermostat to ensure it’s always functioning.

Breakers: Have you had a power outage or surge recently? If your furnace is out, a breaker may have tripped for a variety of reasons.

Filters: A dirty filter can obstruct the furnace’s airflow. The furnace will start to overheat and automatically shut itself off. Regularly changing or cleaning the filters will help your furnace function properly.

Gas: Has the gas valve been shut off? Did you pay your gas bill? If the gas isn’t flowing correctly for whatever reason, the furnace will not run.

Drain hose: Check the drain hose on the furnace. If it’s obstructed with sediment, the furnace will shut off.

Register: A restricted register will obstruct the furnace’s airflow, which may cause it to shut off.

Exhaust flue: An obstructed exhaust flue will cause the furnace to turn off. If the furnace is out, make sure leaves, twigs, bird nests and the like aren’t obstructing the flue.

Obstructed exhaust and intake fans: Debris or stored boxes and equipment can block airflow to the furnace. Clear all things away from the exhaust and intake fans.